Electrical heating of storage and transportation system of a viscous fluid



H. A. LINES Dec. 10, 1940.

ELECTRICAL HEATING OF STORAGE AND TRANSPORTATION SYSTEM OF A VISCOUS FLUID Filed May 12, 1938 Patented Dec. 10, 1940 UNITED STATES PATENT OFFICE ELECTRICAL HEATING F STORAGE AND TRANSPORTATION SYSTEM OF A VISCOUS FLUID Harold A. Lines, West Haven, Comm, asslgnor of One-half to Albert G. Purdue, New Haven, Conn.

Application May 12, 1938, Serial No. 207,423

16 Claims.

This invention relates to the heating of storage and transportation systems for viscous liquids, and more particularly to the application of heat by electrical means to the conductors in which the liquid is transported, whereby the vis-- the liquid, difiiculty is often encountered not only 7 in Starting the flow due to the inherent resistance of the liquid-to flow, but also in maintaining a steady and constant flow without the main tenance of an excessively high pressure. This is particularly true in the transportation of heavy fuel oils, for example, from a storage tank to a burner where the oil is to be used, and is of course also true in the transportation of other viscous liquids such as castor oil, molasses, etc.

I have found that by electrical heating of the conductors or pipes in which the liquid is carried, the viscosity of the liquid may be reduced, and, moreover, that as the heating of the liquid is accomplished adjacent the wall of the conductor ,or pipe, the friction with the pipe is greatly reduced, resulting in a much more efficient handling of the liquid. Moreover, by arranging the liquid conductors, which will usually be of electrically conducting material, in a circuit between thesource of supply and point of delivery, and by immersing the ends of the conductors in the supply or storage tank, the conductors themselves will comprise the greater part of the electrical circuit, and at the same time the liquid lying within the pipes which are immersed in the supply in the storage tank will also be heated, thus providing for prompt initiation of the flow through the conductors.

One object of the present invention is the provision of an improved means for electrically heat, ing storage and transportation systems for viscous liquids.

A still further object of the invention is the provision of a transportation system for viscous liquids which in itself comprises an electrically conducting circuit between the point of supply and point of delivery, so that an electric current passed through the system will serve to heat the liquid during transportation, and thereby render the transportation less difllcult.

A still further object of the invention is the provision of a system for transporting a viscous liquid from a point of supply to a point of delivery such that two liquid conductors will be employed, which conductors will be immersed in the storage or Supply tank at one end, the conductors being so arranged as to form an electrical circuit whereby, when a current is passed through this circuit, the liquid in the storage tank lying within the conductors will be heated, 1

as well as the liquid'within the conductors and without the storage tank, thereby providing for the easy starting and flow of the liquid through the system.

in the novel features and combinations of parts to be hereinafter described and claimed.

In the drawing:

Fig. 1 is a diagrammatic view of an electrically heated storage and transportation system for viscous liquids embodying my invention;

Fig. 2' is a sectional view oi. the storage tank and liquid conductors extending therein;

Fig. 3 is a bottom plan view of the pipe assembly shown in Fig. 2; and

Fig. 4 is a view similar to Fig. 1, showing a somewhat modified form.

To show a preferred embodiment of my invention, I have illustrated a system for the transportation of heavy oils such as fuel oil, for example. It is to be understood, however, that the invention is not limited in respect to the particular liquid which is being conveyed, but is applicable to other liquids as well. It will also be understood that, while I have illustrated a storage tank for fuel oil, and an oil burner to which the oil is to be delivered, the invention is not limited in this respect, but may be applied to the conveyance of a viscous liquid from any point of supply to a point of delivery, which latter may, of course, be a tank to receive the same.

In Fig. 1 of the drawing, I have shown a supply or storage tank I ll wherein fuel oil may be kept to a desired level, to be supplied to an oil burner shown diagrammatically at H. Liquid conductors such as pipes l2, l3 and I4 extend between the storage tank I!) and the burner II, and at a suitable point in the system a pump l5 may be installed to draw the oil from the storage tank and supply it to the burner.

In systems of this character it is common practice to employ a pump which is capable of delivering an excess of oil to the burner, this excess returning to the storage tank through the pipe or conductor I4. For this purpose the pipes To these and other ends the invention consists l2 and N are connected with the tank, as shown in Fig. 2, in a manner which will now be described. The tank is provided with an opening l8 through which is inserted a unit comprising an outer pipe l1 and an inner pipe 18, the lower end of this unit being immersed within the oil in the tank and extending to a point adjacent the bottom 0! the tank, so that the lower end of the pipe II will normally be below the level of the oil. The pipe I2 is arranged to communicate with the pipe l8, while the pipe It is connected to and delivers into the pipe l1, so that the oil returning through the pipe ll will be delivered to the tank around the supply pipe or pump inlet pipe l8.

This unit may be secured in position in any suitable manner, such, for example, as being connected to a cap IS, in turn secured to the tank Ill but insulated therefrom by means of the insulating gasket 20. At the upper end 01 the pipe II the space between it and the pipe i8 is filled by a spacing collar 2|, also of insulating material, so that the pipes I1 and I8 will be insulated from each other at this point, and will, of course, also be insulated from the tank [0.

At the lower end of the pipe I8 the latter is slotted or cut away to provide a pair of downwardly extending tongues 22 and 23. These tongues may be bent outwardly and secured to the wall of the pipe I! by any suitable means, such as brazing or soldering, so that the pipes l1 and I8 will be electrically connected at their lower ends, which are immersed within the oil in the tank I. It will, of course, be understood that a suitable electrical connection between these pipes may be made in any desirable way without departing from the spirit of the invention.

It will thus be apparent that the pipes l2, l3 and I will form an electrical circuit, as these members will normally be constructed of conducting material. The pipe [3 forms, as shown, a continuation of the pipe l2, and will normally be electrically connected to the pipe I through the pump ii. If desired, however, an electrical connector may extend between the pipes l3 and I4 adjacent the outlet end of the system it the structure of the pump will not serve to make a good connection. I

In order to effect an opening in the electrical circuit formed by the system to permit the passage of a current therethrough, an insulating member 25 may be inserted between the pipes l2 and I3, so as to electrically insulate one of these conductor sections from the other. Electric current may be supplied to the sections l2 and II by means of the leads 26 and 21 from the secondary of a transformer 28, the primary coil of which is provided with leads 28 and running to a source of alternating current. It will be apparent that, when current is supplied to the transformer through the leads 29 and 30, a current will be passed through the conductor system comprising pipes l2, I3 and I4, and that this current will also traverse the pipes I1 and i8 through the connections 22 and 23.

In order that the heating of the liquid con-,

ductors may be controlled so that the liquid will always be kept in the proper condition to flow without wastage of current or the use of an excessive amount of current, a thermostat 3i is provided at some point in the system, which will be controlled by the temperature of one of the pipes, l2, for example, as shown in Fig. 1. This thermostat is, as shown, connected with the lead 30 from the primary oi the transformer so as to 22, so as to prevent the loss 0! heat by radiation therefrom, and thus render the system more eifective.

In Fig. 4 of the drawing I have shown a somewhat modiiied form of my invention, wherein the pump is omitted, and the flow oi the liquid is eii'ected by gravity. In this form of my invention the liquid conduits extending irom the storage tank H) to the burner l I will both serve to convey the liquid to the latter nstead of being supply and return lines, as is the case with the structure shown in Fig. 1. There will preferably be, however, two lines oi supply leading irom the tank to the burner, so that an electrical circuit will be formed by these lines, which, in this instance, comprise the pipe sections 35, 26, I1, 38, 39 and 40.

The pipes and 40 will, at their supply ends, be connected to the pipes l0 and ll of a unit extending into the bottom of the supply tank I0, and this unit is constructed as shown and described in connection with the form of my invention shown in Figs. 1 to 3. It will be apparent that this unit will be immersed in the oil within the tank, and will receive oil at its inner end to be conducted by the two supply lines to the burner II, and that the two supply lines will form an electrical circuit which will include the pipes l1 and I8, so that the heating electrically of this circuit will also heat the liquid lying within those portions of the pipes I1 and I! which are within the tank.

In some instances it may be desirable to heat certain sections only of the conductor pipes, rather than the entire conductor system. Such an arrangement is shown in Fig. 4, where the pipe sections are insulated at 4|, I2, 43 and 44. The leads 26 and 21 from the secondary of the transformer 28 are connected to the sections 31 and 35, thus bridging the insulated section 38. A conductor 45 may extend from the section I! to the section 40 around the section 38, so that no current will be passed through the latter section. It will be seen that with this arrangement zone heating of the system will be eflected,

and the sections :1, as and as, 40 adjacent the supply and delivery ends of the system will be heated, while the intermediate sections 36 and 39 will not be. It will. of course, be understood that any zoning arrangement desired may be provided for. It will usually, however, be desirable to include the pipes I1 and 18 within the electrical circuit, so that the supply liquid within these pipes will be heated in order to initiate the how of liquid irom the supply tank. A thermostat 3I may also be provided in this instance to control the supply of electrical current to the transformer.

It will be apparent that in both forms of my invention shown I have provided a transportation system for viscous fluids extending from a point of supply to a point of delivery, the liquid conductors employed in the system forming an electrical circuit which includes a unit immersed within the supply liquid, so that whenan electric current is supplied to the circuit, the liquid conductors, and therefore the liquid, will be heated to reduce the viscosity of the latter and reduce its friction with the conductors or pipes. Also, as the circuit includes the liquid conductors which are immersed within the liquid in the storage tank, that part of the liquid in the tank which lies within these conductors will be heated so as to enable the flow to start, thus effecting, as it were, a self-starting system of transportation.

While I have shown and described some preferred embodiments of my invention, it will be understood that it is not to be limited to all of the details shown, but is capable of modification and variation within the spirit of the invention and within the scope of the appended claims.

What I claim is:

1. Means for transporting a viscous liquid comprising a supply tank, a device to which the liquid is to be transported, a liquid conduit of conducting material connecting said device and tank, the intake end of the conduit having a substantial portion extending into the tank and immersed in the liquid in the tank, and means to pass an electric current through said conduit including the immersed portion thereof to heat the liquid locally therein and lessen its viscosity and thereby initiate flow of the liquid through the conduit.

2. Means for transporting a viscous liquid comprising a supply tank, a device to which the liquid is to be transported, a liquid conduit of conducting material connecting said device and tank, a substantial portion of the end of said conduit being extended into the tank to be immersed in the liquid in the tank, means to pass an electric current through said conduit including an exterior and to be immersed portion thereof to heat the liquid locally in such portions and lessen its viscosity and thereby initiate flow of the liquid through the conduit, and a pump arranged exteriorly of said supply tank to draw the heated liquid therefrom through said conduit.

3. In a transportation system for viscous liquids, a supply tank, a device to receive liquid from'said tank, supply and return pipes of conducting material connecting said tank and device, the ends of which are immersed in the fluid in the tank, a pump to draw fluid from said tank and deliver it to said device, means electrically connecting the ends of said pipes within the tank to form an electrical circuit, means to pass a current through said circuit to heat said pipes and the liquid therein, and the outlet end of said return being located adjacent the inlet end of the supply pipe whereby the heated liquid return to the tank is again drawn into said supply pipe.

4. The method of transporting fuel oil or the like from a supply tank to a burner, comprising passing said oil in excess quantity through a pipe line from the tank to the burner and returning the excess to the tank, electrically heating the pipe line during transit of the oil from the tank to the burner and return, and delivering the excess heated oil to the tank at a point adjacent the pump inlet whereby heated oil is again drawn into the inlet without being diflused through the colder oil in the tank.

5. The method of transporting fuel oil or the like from a supply tank through a conduit, comprising immersing'asubstantial portion of the end of said conduit in the 011 within the tank, and efiecting heating of the oil locally'within the tank and in the conduit by passing an electrical current through the conduit including an immersed part thereof within the tank.

6. In combination, a fluid storage tank, a device to receive fluid conveyed thereto from said tank, a pair of fluid conduits of conducting material connecting said device and tank, a pair of conduits within the tank having passages to which the first-named conduits are connected respectively, said second-named conduits being electrically connected within the tank independently of the fluid therein whereby they form an vly connected independently of the fluid within the tank, and means for passing an electrical current through said conduits whereby the fluid lying within the immersed portions thereof will be heated.

8. In combination, a supply tank adapted to contain a fluid, a unit electrically insulated from the tank and extending thereinto to be immersed in the fluid therein, said unit comprising inner and outerfluid-conducting members of electrical conducting material, said members being spaced from each other but electrically connected adjacent their ends within the tank, a device to receive fluid conveyed thereto from the tank, a pair of fluid conduits of conducting material leading from said unit to said device, said conduits with the fluid conducting members of said unit forming an electrical circuit, and means for passing an electric current through said circuit to heat the fluid therein, including the'fluid lying within said unit in the tank.

9. In combination, a supply tank adapted to contain a fluid, a unit electrically insulated from the tank and extending theneinto to be immersed in the fluid therein, said unit comprising inner and. outer fluid-conducting members of electrical conducting material, said members being spaced from each other but electrically connected adjacent their ends within the tank, a device to receive fluid conveyed thereto from the tank, a pair of fluid conduits of conducting material leading from said unit to said device, insulating means separating adjacent sections of said conduits to break the electrical connection therebetween, and means for passing an electrical current through some of said sections only to heat the fluid passing through such sections and including the fluid within the unit in the tank.

10. In an oil heating system, a supply tank, a

burner, a unit comprising a pair of pipes projecting from the tank and having their inner ends immersed within the fluid therein, said pipes being spaced apart but electrically connected adjacent their inner ends and being insulated from the tank, a pair of pipes leading to the burner and connected respectively with said first-named pipes, all of said pipes being of-conducting material and forming an electrical circuit, and means for passing a current through said circuit independently of the fluid within the tank to heat the fluid therein, including that within the unit in the tank.

11. In an oil heating system, a supply tank, a burner, a unit comprising a pair of pipes projecting from the tank and having their inner ends passing a current through said circuit to heat the fluid therein, including that within the unit in the tank, and temperature-controlled means for controlling the supply of current to the circuit.

12. In an oil heating system, a supply tank, a burner, a unit comprising a pair of pipes projecting from the tank and having their inner ends immersed within the fluid therein, said pipes being spaced apart but electrically connected adjacent their inner ends and being insulated from the tank, a pair of pipes leading to the burner and connected respectively with said first-named pipes, all of said pipes being of conducting material and forming an electrical circuit, means for passing a current through said circuit to heat the fluid therein, including that within the unit in the tank, and means for by-passing the current around certain sections of the pipes.

13. In an oil burner system, a supply tank, a burner, a pair of pipes connecting said burner with the tank, a pump to force oil from said tank to the burner, one of said pipes constituting a return line and the other constituting a supply line, and said pipes being immersed in the oil within the tank and electrically connected at their immersed portions to form an electrical circuit, and being insulated from the tank, adjacent sections of one of said pipes being insulated from each other to break the circuit at that point, a source of current, and leads from said source to said pipe sections on either side of said insulation to pass a current through the pipes and heat the liquid therein, including that within the immersed ends of the pipes.

14. In a transportation system for viscous liquid, a supply tank, a device to which the liquid is to be transported from the tank, supply and return pipes of conducting material connecting said tank and device, the end of said supply pipe being immersed in the liquid in the tank, means to draw the liquid from the tank and deliver it to said device, means electrically connecting said pipes to form an electrical circuit and to pass a current therethrough to heat the pipes and the liquid therein, and the outlet oi said return pipe being directed adjacent the inlet end of the supply pipe whereby the heated liquid returned to the tank is redrawn into the system without being diffused through the cold liquid in the tank.

15. In a transportation system for viscous liquid, a supply tank, a device to which the liquid is to be transported from the tank, supply and return pipes of conducting material connecting said tank and device, the end of said supply pipe being immersed in the liquid in the tank, means to draw the liquid from the tank and deliver it to said device, electrical means for heating said supply and return pipes to heat the liquid therein, and the outlet of the return pipe being located adjacent the inlet of the supply pipe whereby heated liquid discharged from the return pipe is redrawn into the system without being dliiused through the colder liquid in the tank.

16. In a device for transporting oil, a tank having an opening therein, a device to which the oil is to be carried, a cap for said opening electrically insulated irom the tank, supply and return pipes passing through and carried by said cap and connecting the tank with said device, means electrically connecting said pipes adjacent the tank, and means to pass an electric current through the pipe to heat the oil therein.

HAROLD A. LINES. 

